Automatic station tuning apparatus



Oct. 7, 1941.

J. J. MAURO. 7 2,258,024

AUTOMATIC STATION TUNING APPARATUS Filed Oct. 17, 1940 6 Sheets-Sheet l INVENTOR. JOHNJ M40220.

7 I I ATTORNEY.

Oct.'7, 1941.

J. J. MAURO AUTOMATIC STATION TUNING APPARATUS Filed Oct. 17, '1940 6 Sheets- Sheet 2 mob INVENTOR;

I c/DHW J A LACZRO.

1941- J. J. MAURO.

AUTOMATIC STATION TUNING APPARATUS 6 Sheets-Shet 3 Filed Oct. 17, 1940 IN VEN TOR. JOHN :L MAURO.

A TTORNE Y Oct. 7, 1941. J. J. MAURO I 2,258,024

AUTOMATIC STATION TUNING APPARATUS 'Filed Oct. 17, 1940 6 Sheets-Sheet 4 II VVENTOR.

' JOHN J. AMURQ.

Oct. 7, 1941.-

J. J. MAURO AUTOMATIC STATION TUNING APPARATUS Filed Oct 17, 1940 6 Sheets-Sheet 5 VBY Oct. 7, 1941.

J. J. MAURO 2,258,024

AUTOMATIC STATION TUNING APPARATUS Filed Oct. l' 7, 1940 6 Sheets-Sheet 6 "'"ORNEYS.

Patented Oct. 7, 1941 UNITED STATES PATENT OFFICE (Granted under the act of March 3, 1883, as

amended April 30, 1928; 370 O. G. 757) 12 Claims.

This invention relates to the art of producing and controlling successive operations of variable magnitude at predetermined intervals over a period of time, as for example, to controlling a radio receiving set for tuning in only selected stations at some or all of the broadcasting periods for an entire day or for any portion or portions thereof.

Important objects of the invention are to provide for greater convenience of the user of apparatus of the class described by making it possible to select, by setting or adjustment of the apparatus at one time, the operations desired for quite a considerable period so that the apparatus may function as intended during that period without attention from the operator or user; to provide apparatus of this general class which is particularly adapted for installation in a radio receiving set for producing and controlling the operations of adjusting the tuning means of the set for selected intervals over a given period; and also to provide apparatus of the class described having an improved construction and relative arrangement of parts.

The invention provides for using a motor for making desired adjustments or settings at selected intervals and controlling the duration of the period of operation of the motor and therefore the extent of the adjustment at each selected interval by having the motor also cause one of a plurality of previously adjusted members to traverse in engagement with a contact or segment, which controls the motor circuit, from the initial position of such member substantially to the end of such contact or segment, so that the circuit is completed and the motor operates only during such traversing engagement of the member and the contact or segment. Engagement only at selected intervals may be effected between one of the previously adjusted members and a particular contact or segment controlling the motor circuit by actuating means subject to a suitable time control for intermittently producing relative movement between the previously adjusted member or members and a particular contact or segment. Any desired adjustment once effected may be retained for the interval between the time controlled relative movement and for any multiple thereof, by previous adjustment to a neutral or "off position of a suitable number of the contact engaging members so that the latter do not engage a controlling contact or segment and the motor therefore, does not operate to change the adjustment. This makes it possible, when using this apparatus with a radio receiving set, to retain a selected radio station, for example, for a number of intervals, such as the usual 15-minute periods of broadcasting stations.

The features of the invention are illustrated in the accompanying drawings, wherein:

Figs. 1, 2 and. 3 are plan views, with parts omitted and broken away for the purposes of illustration, of the lower portion of apparatus of my automatic station tuning device described herein;

Fig. 4 is a fragmentary plan view to a larger scale illustrating sets of segmental contacts and cooperating means for effecting engagement and disengagement thereof;

Fig. 5 is a perspective view of the pairs of segmental contacts shown in Fig. 4 with a cooperating gear and a member for effecting engagement of these contacts;

Fig. 6 is a plan view, with parts omitted and broken away for purposes of illustration, of mechanism forming the upper portion of the automatic station tuning apparatus described her in;

Fig. 7 is a view taken on the line 7-'l of Fig. 6;

Fig. 8 is a fragmentary plan view illustrating a detail of construction;

Fig. 9 is a section taken on the line 9-9 of Fig. 6;

Fig. 10 is a fragmentary elevational view showing an anchor escapement and a face dial I stantially along the line of !2-l2 of Fig. 1, parts being omitted and broken away for purposes of illustration Fig. 13 is a rear elevational View of an upstanding bracket shown in Fig. 6, illustrating the mounting of a pair of electromagnets and cooperating mechanism;

Fig. 14 is a front elevational view of the bracket shown in Fig. 13 and mechanism supported thereby, parts being omitted and broken away for purposes of illustration;

Fig. 15 is a wiring diagram of the circuits and devices for operating this automatic station tun ing apparatus;

Fig. 16 is a front elevational View of the upper portion of the cabinet of the radio receiving set;

Fig. 17 is a view illustrating a portion of the mechanism shown in Fig. 3, to a larger scale;

Fig, 18 is an enlarged detailed View of a portion of the structure shown in Fig. 5;

Fig. 19 is a section on line I9-I9 of Fig. 13; and

Fig. 20 is an elevational view partly in section illustrating a detail of construction.

The embodiment selected for illustration is adapted to be installed in a cabinet I (Fig. 16) of a radio receiving set having a tuning means here shown as comprising cooperating fixed and movable condenser plates II and I2 (Fig. 6), respectively, the latter being fixedly mounted on a rotary shaft I3 extending through the front wall of the cabinet I6 and journalled in a suitable bearing I4 mounted preferably on the inner side of this wall. The protruding end of this shaft may be equipped with suitable means, such as a knob I6, for facilitating manual adjustment of shaft I3 and the movable condenser plates I2 carried thereby. For automatically adjusting the condenser plates there is provided a motor I1, preferably of the reversible type, having its shaft I8 supported in a bearing I9 mounted on any fixed support, as upon an upstanding bracket 2| (Figs. 6, 7, 9, 11-14). Preferably, this bracket is provided with end walls 22 and 23 in which a shaft 24 is rotatably mounted. Mitre gearing 26 may be provided for transmitting rotary motion between the motor shaft and shaft 24, and similarly, mitre gearing 21 may be provided for transmitting rotary motion between shafts 24 and I3.

The extent of each automatic adjustment of the tuning means, as of the movable condenser plates I2, may be determined by limiting the period of operation of the motor for each such adjustment. This may be accomplished by providing, in the motor circuit, normally open contacts which are closed only for a sufficient time at each adjustment interval to permit the motor to make the desired adjustment. When using a reversible motor, as shown, there may be one set of these contacts in each of the circuits which controls the motor in its two directions of operation.

Preferably, these contacts are in the form of opposed pairs of cooperating, inner and outer arcuate contacts or segments 28, 29, 3| and 32 (Figs. 5, 11 and 18), respectively, arranged with the adjacent ends of the contacts of each pair spaced from opposed adjacent ends of the contacts of the other pair to leave open spaces or gaps 33 and 34 preferably 180 degrees apart. The contacts of each pair may be normally urged apart by means of a suitable number of radially disposed and circumferentially spaced expansible springs 36 mounted on similarly spaced insulated pins 31 and 38 (Fig. 18) carried, respectively by the inner and outer contacts. Preferably, each of the outer contacts 29 and 3I is formed, respectively as a part of a supporting standard 39 and M equipped with suitable base plates or attaching flanges 42 and 43, respectively.

A pair of circumferentially extending insulated flat plates 44 and 46 may be secured in any suitable manner to the sides of outer contact 29 so as to extend inwardly therefrom to embrace inner contact 28 and provide a guideway in which this inner contact may move radially. The outer pins 38 for the springs 36 may be mounted, as shown, to extend directly through these plates so as to secure these plates to outer contact 29. These plates may be provided with substantially radial slots 41 through which the inner pins 31 may extend to provide for substantially radial movement of this inner contact. In a like manner, circumferentially extending insulated flat plates 48 and 49 may be secured by pins 38 associated therewith to outer contact 3| to extend inwardly therefrom about inner contact 32 to provide a radial guideway therefor. These plates may be provided With substantially radial slots 41 for the inner pins 31 as described with reference to plates 44 and 46.

For effecting engagement of the contacts just described, there may be provided a plurality of members, preferably in the form of substantially radial arms or pendants 5| (Figs. 1, 4, 5, 11 and 12), each secured individually to one of a corresponding number of gears 52 rotatably mounted upon a fixed shaft 53, as by means of hub portions 54 which also serve as a means for spacing these gears and their attached members 5| longitudinally of shaft 53. This shaft may be mounted in movable end brackets 56 and 51 (Fig. 12) by means of keys and washers 58 and 59 on the outer sides of these brackets and spacing sleeves SI and 62 disposed between the outermost hub portions of the series and the adjacent one of brackets 56 and 51. Each of these brackets may be provided with laterally spaced webs or flanges 63, 64, 66 and 61 (Fig. 7) in which are mounted axles 68 carrying wheels 69 adapted to ride on rails 1I. It will be seen that these movable end brackets and the shaft 53 mounted thereon constitute a movable carriage for supporting the members 5| for movement relative to the contacts 2832 (Fig. 5). For further bracing this carriage a bar 12 (Fig. 1) may be attached to the end brackets adjacent the ends of the axles on one side thereof and on the opposite side in a similar position a rack 13 may be attached to the end brackets 56 and 51. A vertically disposed plate 14 (Figs. 11 and 12) extends longitudinally beneath shaft 53 and is secured to end brackets 58 and 51 as by means of laterally extending flanges 16 and 11 and suitable attaching elements (not shown). This plate may be provided with vertically disposed slots 18 spaced to receive gears 52 for assisting in spacing the latter. In order to assure that the carriage will not leave the rails H a horizontal rod 19 (Fig. 12) may be secured in fixed brackets 8| (Fig. 12) and 82 (Fig. 6) and arranged to extend through openings 83 and 84 in the upper portions of movable brackets 56 and 51. Preferably openings 83 and 84 are of a size to have a free running fit with rod 19. The carriage supporting rails 1| may also be secured to fixed brackets BI and 82 and otherwise attached to the framework, as by being secured to the base 86 of the cabinet.

For moving the carriage just described, a pinion 81 fixed on a shaft 88 (Figs. 1, 2 and 9) may be arranged to engage rack 13 attached to the carriage. A gear 89 fixed on shaft 88 meshes with a pinion 9I (Fig. 9) fixed on a shaft 92 which is connected to and operated by time control mechanism 93, such as a clock, Telechron, or the like. For preventing overrunning of the time control mechanism, a ratchet 94 may be fixed on shaft 88 adjacent the time control mechanism and a double pawl 96 (Fig. 10) may be pivotally mounted on a fixed pivot 91 in the form of a shaft (Fig. 2) mounted on the time control mechanism and on the front panel of the cabinet II). A retractile spring 98 may be connected to a fixed pin 99 and to the longer arm of the pawl, as shown, so that this pawl and its cooperating ratchet may operate in the well known manner to provide for advance of the carriage with a definite step by step motion. For manually adjusting the position of the carriage, shaft 88 may be arranged to extend through the front panel of cabinet I and be equipped with a manually operable knob IN. A bearing I02 may be mounted on the inner wall of this panel for rotatably Supporting this shaft.

In order that the position of the carriage may be known at any time to the operator or user, a dial I03 (Figs. 6 and may be rotatably mounted in the front wall of cabinet I0, as by being disposed in an annular recess in the rear surface of said wall and held therein by an overlying retaining ring I04 secured to this wall in any suitable manner, as by attaching elements I06. This dial may be graduated to indicate the time of day over a given period, as in minute intervals over a 24 hour period. An observation opening I07 may be provided in the cabinet wall opposite this dial, and preferably opposite the upper median portion thereof as shown. For adjusting this dial to make such timecorrections as may be desirable, a gear I08 may be affixed to the rear face thereof, as by attaching elements I09, and arranged to mesh with a gear III (Fig. 6) fixed on a rotary shaft II2 mounted in a bearing II3, carried by the time control mechanism, and extending through the front panel of cabinet I0 and equipped on its outer end with a manually operable knob H4. 5

Motion may be transmitted between dial I03 and shaft 88 (Fig. 9) and rack 13 through a friction clutch comprising an element II6 fixed on a rotary shaft II'I havin one end afiixed to dial I03 and the other end thereof rotatably supported in a bearing 8 mounted on the time control mechanism. The other element II9 of this friction clutch may be affixed to a gear I2I rotatably mounted on shaft I I1 and meshing with a pinion I22 aflixed to shaft 88. This clutch, comprising cooperating elements H6 and H9, is so constructed and adjusted that when knob H4 is turned to adjust the dial, the elements of the clutch will slip and, hence, gear I2I remains stationary under the resistance to motion imposed thereon by the movable carriage through rack I3, gear 81, shaft 80 and gear I22 meshing with gear I2I. However, when knob IOI is turned or time control mechanism 93 operates shaft 68, the latter functions through gears I22 and I2I andelements H9 and H6 of the friction clutch to rotate dial I03 in proportion to movement of the carriage.

During operation of motor N (Fig. 6), rotary motion may be transmitted from motor operated shaft 24 to one of the members 5I attached to a gear 52 (Fig. 11) by means of a gear I26 fixed on shaft 24 (Figs. 6 and 11) and meshing with an idler gear IZ'I fixed on a rotary shaft I28 and a gear I29 rotatably mounted on a n on-rotatable shaft I3I. To provide for engagement and disengagement of gear I29 and the selectedone of gears 52, shafts I28 and I3I may be mounted for transverse bodily movement toward and from gears 52. This may be accomplished by means of a swinging frame comprising spaced side members I32 and I33 (Figs. 3, 6 and 11) pivotally supported on shaft 24 for pendulous motion about the axis thereof.

Preferably, shaft I28 carrying gear I2! is of such a length (Fig. 14) that it may be entirely disposed within the space between the end walls 22 and 23 of upstanding bracket 2I and rotatably mounted in these swinging side frames I32 and I33, as shown, while shaft I3I is non-rotatably supported on swinging side frames I32 and I33 and has its ends extending through substantially horizontally disposed slots I40 (Fig. 7) in end walls 22 and 23 and projecting outwardly through somewhat elliptical flanges or collars I30 and I30, fixedly mounted on end walls 22 and 23, respectively. For effectively holding shaft I3I from objectionable endwise movement without interfering with the desired horizontal transverse movement thereof, horizontally disposed, headed pins I35, I35 may be slidably mounted in collars or flanges I30 and I3I and fixedly mounted in the end portions of shaft I3 I, so that as this shaft moves transversely, the heads on these pins serve as abutments which may engage the exterior surfaces of collars I30, I39 to fix or limit the extent of this movement. This transverse motion may also be limited to a small arc by means of a pair of pin and slot connections I34 and I36 (Figs. 3, 11 and 17) between a laterally extending web I31 carried by upstanding bracket 2|, and ears I38 and I39 carried respectively by thimbles MI and I42. Preferably, pin and slot connections I34 and I36 are loose enough to avoid objectionable binding at these points. A pair of retractile springs I43 (Fig. 3) may be connected between frame members I32 and I33 and fixed pins I44 mounted on upstanding bracket 2|. These springs (I43) normally urge gear I29 into a position where it is disengaged from a juxtaposed gear 52.

Gear I29 may be moved into engagement with an aligned gear 52 as the motor starts and disengaged therefrom as the motor stops by means of the mechanism shown in Figs. 3 and 14. This mechanism comprises expansible springs I and I4! disposed about shaft I3I and seating at their inner ends against a vertically disposed plate I48 fixedly mounted on web I3! on upstanding bracket 2!. At their outer ends these springs seat against rollers I49 which are freely rotatable on shaft I3I. Sleeves I5I and I52 mounted on shaft I3I for travel longitudinally therealong are provided respectively with flanges I53 and I54 which bear against the adjacent sides of rollers I49 and have frictional, sliding engagement therewith. These sle-eves have oppositely disposed, exterior helical threads I56 and I51, respectively, which engage complementary interior threads I58 and I59, respectively, in stationary thimbles MI and I42. Adjacent rollers I49, web I3! is formed with a cam surface comprising recesses or depressions I6I and I62 and a rise I93.

When the motor is not operating both of the rollers I49 are disposed in the end depressions of this cam surface, but when the motor operates gear I 29 in either direction, one of the sleeves (i5I or I52) is forced out of its thimble and causes the roller I49 associated therewith to ride up on the rise I63 and thus imparts bodily movement to shaft I3I and gear I29, causing the latter to swing into its position for engagement with one of gears 52. When the motor stops, that one of the springs I46 and I47, which was compressed by the action just described, returns its associated roller to its depression in the cam surface and springs I43 retract, moving, side frame members I 32 and I33 away from gears 52 and, hence. gear I29 is disengaged from one of gears 52. Gear I 29 is never intended to make more than part of a complete revolution.

In accordance with this invention, electrical circuits and apparatus may be provided as shown e I in Fig. 15. As illustrated, this equipment comprises the reversible motor 1?, a voltage reducing transformer I76, electromagnets Ill, I18, their associated armatures I19, IEI carrying contacts I82, I63, I84 and IE6 for engagement with stationary contacts I81, I66, I89 and IQI; the cooperating segmental contacts 28, 29, 3I and 32, a gear 52 and a member 5I associated therewith and with said segmental contacts; and also an electrically operated time control device I92, such as a Telechron. Electrical energy may be supplied to these devices from lines I93 and I94 connected to any suitable source, preferably to the samesource which supplies electrical energy to the receiving set so as to be controlled by the same switch which turns the receiving set on and off. These lines may be connected directly to the time control device I 92 by connections 241 and 248.

Electrical energy may be supplied to the motor from lines I93 and I94 through connections I96 and I91 to connections I98 and I99. From the motor, connections 20I and 202 lead to contacts I84 and I86 of armature I8I and connections 203 and 204 lead to contacts I89 and I9I. When the circuit is completed from connection 20I through contacts I84 and I89 to connection 203, and from connection 202 through contacts I86 and I 9| to connection 204, the motor will operate in one direction. When this circuit is open at these contacts a circuit is completed from the motor through connections 206, 201, contacts I82, I83, I81 and I88 to connections 208 and 209, the motor will operate in the reverse direction.

The lower stationary contacts I81, I88, I89 and I9I may be supported on a bracket 2II (Figs. 7 and 13) mounted on the rear wall of upstanding bracket 2I. The armatures I19 and I8I may be mounted on the arms of a yoke 2I2 mounted on a pivot 2I3 carried by a bracket 2I4 afhxed to the rear of upstanding bracket 2I (Fig. 13). The electromagnets I11 and I18 may also be attached to the rear of upstanding bracket 2| in any suitable manner (not shown).

Electrical energy for operating electromagnets I11 and I18 may be supplied from lines I93 and E94 through connections I96, I91, I98, I99, 2I6 and 2I1 to the primary (not shown) of transformer I18. From the secondary (not shown) of this transformer a circuit leads through connection 2I8 to terminal 2I9 of electromagnet I 18, through winding 220 of the latter to terminal 22I thereof, thence through connection 222 to inner segmental contact 28, to outer se mental contact 29 and through connection 223 back to the secondaly of the transformer. Another circuit leads from the secondary of the transformer through connection 228 to terminal 221 of electromagnet I11, through winding 228 thereof to terminal 229, through connection 23I to inner segmental contact 30, outer segmental contact 32 and connection 232 back to the secondary of the transformer. It will be seen that when the circuit is completed through segmental contacts 28 and 29, electromagnet I18 will be energized, and when a circuit is completed through segmental contacts SI and 32, electromagnet I11 will be energized.

In order that the receiving set may be shut off when desired, as when the tuning means are in neutral or off position, a normally closed switch may be connected in line I94 by leads 249 and 250 (Fig. 15). Preferably, a suitable voltage regulator 25I is inserted in lines I 93 and I94 ahead of this switch so that these lines may supply electrical energy to the receiving set. This switch (Figs. 6, 8 and 15) may comprise resilient arms 233 and 234 of conducting material normally engaging each other and adapted to be separated to open the circuit by means of an arm 236 of non-conducting material. As shown in Figs. 6 and 8, arm 236 may be carried by a collar 231 on shaft I3, and arms 233 and 234 may be mounted on a strip of non-conducting material 238 secured to any convenient fixed support, as to upstanding bracket 2 I. This switch may be mounted in such a position that during the normal range of rotary movement of shaft I3 for all tuning adjustments of the receiving set, arm 236 does not engage and separate arms 233 and 234, and only when shaft I3 is turned beyond the range of movement which is useful for tuning is it possible for arm 236 to engage and separate arms 233 and 234. As illustrated, this is accomplished by mounting arms 233 and 234 well below the horizontal transverse center line of shaft I3. It will also be understood that a switch of the usual snap action type may be used in place of the one just described, if desired.

In use, this apparatus may be set to tune in selected stations over a given period, as for each 15-minute interval for a 24-hour day by first rotating knob IN to move the carriage to its extreme right hand position as viewed in Fig. 12, in which position segmental contacts 28-32 are disposed about the left hand spacing sleeve 6|. In this arrangement, bracing strip or bar 12 (Fig. 1) of the carriage passes freely through a vertical slot 239 (Fig. 11) in standard M which supports outer segmental contact 3| (Fig. 5) and rack 13 passes freely through an opening 24I in standard 39 which supports outer segmental contact 39, while the carriage supporting rails 1I extend freely through slots 242 and 243 in the base portions of standards 39 and 4 I, respectively, and the vertically disposed and slotted spacing strip 14 for gears 52 extends freely through lower gap 244 between segmental contacts 28-32 (Figs. 5, 11 and 12). The carriage is then returned, by adjusting knob IOI in the opposite direction until the first of the series of gears 52 thereon is disposed in position for engagement with gear I29. As this position is reached the member 5I associated with this gear 52 will either enter the upper gap 33 (Fig. 5) between segmental contacts 28-32 or engage one of the inner segmental contacts 28 or 32 and force it into engagement with its associated outer segmental contact 29 or 3I to complete an electrical circuit through one pair of these contacts, as through contacts 28 and 29 or through contacts 3I and 32. However, as these adjustments are being made the main switch (not shown) for the automatic tuning apparatus should be opened so that no electrical energy is supplied to this electrical equipment.

It will be recalled that as knob IN is adjusted to move the carriage by means of shaft 88, gear 81 and rack 13 (Fig. 9), gear I22 on shaft 88 also engages gear I2I which acts through elements II9, II 6 of the friction clutch to rotate shaft I I 1 and dial I03 to a position in which the latter will expose through observation opening I01 (Figs. 6 and 10) the time at which the first 15- minute interval is to begin. By adjusting knob I6 (Fig. 6) the tuning means may then be set to tune in the station desired for the first 15 minute interval of the 24-hour day, or if no station is desired the tuning means may be adjusted to neutral or'off position which corresponds to a vertical position of member 5| in which the latter is aligned with gap 33 (Fig. 5) for passing freely therethrough without completing a circuit through either of the pairs 28, 29 or 3!, 32 of segmental contacts.

If a station is desired for this first interval the tuning means should also be adjusted first to its neutral or off position in which the first of the 'members register with gap 33. As this adjustment is made the reading of dial I03 should also be checked to ascertain whether it reads correctly, and if it does not, it should be properly adjusted by turning knob II4 which acts through gears III and I98 (Fig. 6) to effect this result without disturbing the position of the carriage due to slippage of elements 6 and N9 of the friction clutch (Figs. 6 and 9), as previously described herein.

As knob I6 is turned to adjust the tuning means through shaft I3, the latter operates through mitre gearing 21 (Fig. 6) to rotate shaft 24 and gear I26 which, through idler I21 (Fig. II) rotates gear I29. As gear I29 rotates, one or the other of rollers I49 (Fig. 3) is forced onto the cam rise I63 by the travel of one of the sleeves I5I, I52 produced by engagement of its external threads I56 or I51 with complementary internal threads in its associated stationary thimble I 4| or I42, which, of course, compresses one of the springs I46 or I41. As one of the rollers I49 rides out onto cam rise I63, shafts I28 and I3I carried by the swinging side frames I32 and I33 and gears I21 and I29 mounted on these shafts swing outwardly to bring gear I29 into engagement with the juxtaposed gear 52. The proper adjustment of the tuning means by knob I6 may be observed on the usual dial provided for this purpose on receiving sets, such as dial 246 (Fig. 16). This adjustment may be in either direction and accordingly it may move gear 52 and its associated member. 5| clockwise or counterclockwise from gap 33, thereby causing this member 5| to engage and travel over one of inner segmental contacts 28 or 32 for a distance corresponding to the adjustment of the tuning means for the selected station. This forces the inner contact (28 or 32) into engagement with its associated outer contact (29 or 3|) during the adjustment.

As the adjustment for the first minute interval is completed in this manner, knob IOI (Fig. 9) is turned to advance the carriage to bring the next of gears 52 into position for engagement with gear I29 and the operations just described are repeated for the second of gears 52, and so on until each of the remaining gears 52 and its associated member 5| have been set for their corresponding 15 minute interval of the 24 hour day. The carriage may then be returned to its extreme right-hand position as shown in Fig. 12, by turning knob I6I (Fig. 9). When this is done the receiving set is ready for operation with automatic tuning.

To put the set in operation, the main switch (not shown) is closed, thus supplying electrical energy to lines I93 and I94 and to the circuits and devices shown in Fig. 15. Intermittently, at the beginning of each 15 minute interval, the time control device I92 acts through gears 9| and 89, shaft 88, gear 81 and rack 13 to advance the carriage to bring the next in order of the gears 52 into position for engagement with gear I29. As this is done, the previously set member 5| associated with this gear engages and forces one of the inner segmental contacts 28 or 32 into engagement with its associated outer contact 29 or 3|, thereby completing a circuit from the secondary of transformer I16 through the winding of one of the electromagnets I18 or I11.

If electromagnet I11 is energized, for example, A

it will attract its armature I19 and through the action of yoke 2|2, this motion will swing downwardly armature I 8| of eletromagnet I18 until contacts I84 and I86 engage contacts I89 and I9I, thereby completing a circuit from motor I1 through connections ZIII, 202, 293 and 264 back to the motor and causing it to operate in one direction. As the motor operates it rotates shaft 24 (Fig. 6) and gears I26, I21 and I29 (Fig. 11). As gear I29 starts to rotate it is swung into engagement with the gear 52 previously positioned for engagement with it by adjustment of the carriage by the time control device. As the motor continues to operate this gear 52 also rotates and causes its associated member 5| to travel along the inner periphery of that one of inner segmental contacts 28 or 32 which it engages until this member 5| falls into gap 33 (Fig. 5) and allows such inner segmental contact to be separated from its cooperating outer segmental contact by the action of expansible springs 36, thereby breaking the circuit and stopping the motor. During this period of operation of the motor, shaft I3 (Fig. 6) is driven continuously from shaft 24 through gearing 21 and the tuning means, such as movable plates I2 are continuously and progressively adjusted. When the motor stops, the adjustment of the tuning means for that particular 15-minute interval is completed. It will be seen, therefore, that the period of operation of the motor and the extent of travel of the particular member 5| determines the extent of the adjustment of the tuning means. It will be understood that when electromagnet I18 is energized by engagement of segmental contacts 28 and 29, a similar action takes place, but the motor operates in the reverse direction to cause a member 5| to travel from a position of adjustment on the opposite side of gap 33 back into this gap.

The invention described herein, if patented, may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

I claim as my invention and desire to secure by my patent:

1. Apparatus of the class described, comprising a reversible motor for adjusting the tuning means of a radio set, circuits for operating said motor in both directions, contact segments associated with said circuits for controlling the latter, a plurality of members angularly adjustable relative to each other for initial engagement with difierent portions of said contact segments, means for holding said members in fixed spaced relation for successive engagement between only one of said members and only one of said contact segments, means for supporting said contact segments and said members for relative movement for effecting engagement successively between each of said members and one or the other of said contact segments, time control means for periodically effecting said relative movement, and means responsive to operation of said motor for causing one of said members engaging one of said contact segments to travel from the point of initial engagement therewith substantially to the end thereof and thereby determine the extent of adjustment of said tuning means.

2. Apparatus of the class described, comprising a reversible motor for adjusting the tuning means of a radio set, circuits for operating said motor in both directions, contact segments associated with said circuits for controlling the latter, a plurality of members angularly adjustable relative to each other for initial engagement with different portions of said contact segments,

means for holding said members in fixed spaced relation for successive engagement between only one of said members and only one of said con tact segments, means for supporting said contact segments and said members for relative movement for effecting engagement successively between each of said members and one or the other of said contact segments, time control means for periodically effecting said relative movement, disengageable gearing for transmitting rotary motion from said motor to each of said members while it engages one of said contact segments, and means responsive to operation of said motor for effecting engagement of said gearing and thereby causing one of said members engaging one of said contact segments to travel from the point of initial engagement therewith substantially to the end thereof and thereby determine the extent of adjustment of said tuning means.

3. Apparatus of the class described, comprising a reversible motor for adjusting the tuning means of a radio set, circuits for operating said motor in both directions, contact segments as sociated with said circuits for controlling the latter, said contact segments being arranged in opposed spaced relation to provide a gap therebetween, a plurality of members angularly adjustable relative to each other for initial engagement with different portions of said contact segments or for passage through said gap when aligned therewith, means for holding said members in fixed spaced relation for successive engagement between only one of said members and only one of said contact segments, means for supporting said contact segments and said members for relative movement for eifecting engagement successively between each of said members and one or the other of said contact se ments or for passage through said gap, time control means for periodically effecting said relative movement, and means responsive to operation of said motor for causing one of said members engaging one of said contact segments to travel from the point of initial engagement therewith substantially to the end thereof and thereby determine the extent of adjustment of said tuning means.

4. Apparatus of the class described, comprise ing a reversible motor for adjusting the tuning means of a radio set, circuits for operating said motor in both directions, contact segments as sociated with said circuits for controlling the latter, a plurality of members angularly adjustable relative to each other for initial engagement with diiferent portions of said contact segments, means for holding said members in fixed spaced relation for successive engagement between only one of said members and only one of said contact segments, a carriage for supporting said members for movement relative to said contact segments for effecting engagement successively between each of said members and one or the other of said contact segments, rails for supporting said carriage for such movement, means for holding said carriage on said rails, time control means for periodically effecting said movement, and means responsive to operation of said motor for causing one of said members engaging one of said contact segments to travel from the point of initial engagement therewith substantially to the end thereof and thereby determine the extent of adjustment of said tuning means.

5. Apparatus of the class described, comprisinga reversible motor for adjusting the tuning means of a radio set, circuits for operating said motor in both directions, contact segments as sociated with said circuits for controlling the latter, a plurality of members angularly adjustable relative to each other for initial engagement with different portions of said contact segments, means for holding said members in fixed spaced relation for successive engagement between only one of said members and only one of said contact segments, a carriage for supporting said members for movement relative to said contact segments for effecting engagement successively between each of said members and one or the other of said contact segments, a rack aflixed to said carriage, a pinion engaging said rack, time control means for periodically actuating said pinion for effecting said movement, independently operable means for actuating said pinion, and means responsive to operation of said motor for causing one of said members engaging one of said contact segments to travel from the point of initial engagement therewith substantially to the end thereof and thereby determine the extent of adjustment of said tuning means.

6. Apparatus of the class described, comprising a reversible motor for adjusting the tuning means of a radio set, circuits for operating said motor in both directions, contact segments associated with said circuits for controlling the latter, a plurality of members angularly adjustable relative to each other for initial engagement with different portions of said contact segments, means for holding said members in fixed spaced relation for successive engagement between only one of said members and only one of said contact segments, a carriage for supporting said members for movement relative to said contact segments for effecting engagement successively between each of said members and one or the other of said contact segments, time control means for periodically eflecting said movement, time indicating means responsive to said movement, and means responsive to operation of said motor for causing one of said members engaging one of said contact segments to travel from the point of initial engagement therewith substantially to the end thereof and thereby determine the extent of adjustment of said tuning means.

7. Apparatus of the class described, comprisinga reversible motor for adjusting the tuning means of a radio set, circuits for operating said motor in both directions, contactsegments associated with said circuits for controlling the latter, a plurality of members angularly adjustable relative to each other for initial engagement with different portions of said contact segments, means for holding said members in fixed spaced relation for successive engagement between only one of said members and only one of said contact segments, a carriage for supporting said members for movement relative to said contact segments for effecting engagement successively between each of said members and one or the other of said contact segments, time control means for periodically effecting said movement, time indicating means responsive to said movement of said carriage, independently operablemeans for moving said time indicating means, and means responsive to operation oi. said motor for causing one of said members engaging one of said contact segments to travel from thepoint of initial engagement therewith substantially to the end thereof and thereby determine the extent of adjustment of said tuning means.

8. Apparatus of the class described, comprising a reversible motor for adjusting the tuning means of a radio set, normally open circuits for controlling the operation of said motor in either direction, means for completing either of said circuits comprising a plurality of rotary members arranged about a common axis for rotary movement and adjustment relative to each other, substantially arcuate members disposed about said axis and said rotary members for cooperative engagement with the latter, said arcuate members being spaced to provide an intervening neutral or off position, means responsive to engagement of one of said rotary members and one of said arcuate members for completing one 01' said circuits, means responsive to engagement of one of said rotary members and the other of said arcuate members for completing the other of said circuits, and means responsive to operation of said motor for causing a rotary member engaging one of said arcuate members to return to said intervening neutral or oii position at a speed proportional to the speed of said motor and thereby to determine the extent of adjustment of said tuning means.

9. Apparatus of the class described, comprising a reversible motor for adjusting the tuning means of a radio set, normally open circuits for controlling the operation of said motor in either direction, means for completing either of said circuits comprising a plurality of rotary members arranged about a common axis for rotary movement and adjustment relative to each other, substantially arcuate members disposed about said axis and said rotary members for cooperative engagement with the latter, said arcuate members being spaced to provide an intervening neutral or off position, means responsive to engagement of one of said rotary members and one of said arcuate members for completing one of said circuits, means responsive to engagement of one of said rotary members and the other of said arcuate members for completing the other of said circuits, means responsive to operation of said motor for causing a rotary member engaging one of said arcuate members to return to said intervening neutral or off position at a speed proportional to the speed of said motor and thereby to determine the extent of adjustment of said tuning means, and time control means for periodically efiecting relative movement between said rotary members and said arcuate members for successively establishing a cooperative relationship between said arcuate members and each of said rotary members.

10. Apparatus of the class described, comprising a reversible motor for adjusting the tuning means of a radio set, normally open circuits for controlling the operation of said motor in either direction, means for completing either of said circuits comprising a plurality of rotary members arranged about a common axis for rotary movement and adjustment relative to each other, substantially arcuate members disposed about said axis and said rotary members for cooperative engagement with the latter, said arcuate members being spaced to provide an intervening neutral or off position, means responsive to engagement of one of said rotary members and one of said arcuate members for completing one 01! said circuits, means responsive to engagement of one of said rotary members and the other of said arcuate members for completing the other of said circuits, means responsive to operation of said motor for causing a rotary member engaging one of said arcuate members to return to said intervening neutral or off position at a speed proportional to the speed of said motor and thereby to determine the extent of adjustment of said tuning means, and a manually operable rack and pinion mechanism for effecting relative movement between said rotary members and said arcuate members for successively establishing a cooperative relationship between said arcuate members and each of said rotary members.

11. Apparatus of the class described, comprising a reversible motor for adjusting the tuning m ans of a radio set, circuits for controlling the operation of said motor in either direction, means for completing either of said circuits comprising a plurality of rotary members arranged about a common axis for rotary movement and adjustment relative to each other, a pair of inner and outer segmental contacts interposed in each of said circuits and oppositely disposed about said axis and said rotary members for cooperative engagement between the latter and the inner contact segments, said pairs of inner and outer segmental contacts being spaced to provide an intervening neutral or off position, each of said pairs of said segmental contacts being effective on engagement of one of said rotary members With the inner contact of said pair for completing the circuit with which said pair is associated, and means responsive to operation of said motor for causing a rotary member engaging one of the inner segmental contacts of said pairs to return to said intervening neutral or off position at a speed proportional to the speed of said motor and thereby to determine the extent of adjustment of said turning means.

12. Apparatus of the class described, comprising a reversible motor i'or adjusting the tuning means of a radio set, circuits for controlling the direction of operation of said motor, a contact associated with each of said circuits for completing or interrupting the circuit with which it is associated, said contacts being spaced to leave a fixed gap providing a neutral or ofi position therebetween, a plurality of members eachof a size to pass freely through said gap when aligned therewith, a carriage movable relative to said contacts, means for supporting said members on said carriage in fixed spaced relation for successive engagement with only one of said contacts and for relative angular movement for alignment with said gap or for engagement with either of said contacts in difierent positions relative thereto so that on movement of said carriage each of said members in succession may either pass freely through said gap or engage one or the other of said contacts, means responsive to operation of said motor for causing a member engaging one of said contacts to return to said intervening neutral or off position at a speed proportional to the speed of said motor and thereby to determine the extent of adjustment of said tuning means, and time control means for periodically moving said carriage relative to said contacts for effecting successive engagements between said members and said contacts.

JOHN J. MAURO. 

